基于离散网络法的接地系统优化计算模型研究

Study on Improved Calculation Model of Grounding System Based on Discrete Network Method

接地系统在雷电冲击下的暂态特性对电网安全稳定运行极为关键。为了实现脉冲电流下复杂接地系统特性诊断及建模,研究了脉冲电流影响下的接地系统传统计算模型、Duhamel积分法和参数逼近法,Duhamel积分法难以表征复杂电路模型,参数逼近法难以获得理想的实验数据近似值。基于离散网络法提出一种接地系统改进计算模型,该方法所建立的模型形式允许其直接运用计算电路暂态过程的现代算法,结果表明该方法计算精度高,易于在计算机中实现,可有效避免传统建模方法中的缺陷。

The transient characteristics of the grounding system under lightning impact are critical to the safe and stable operation of the power grid. In order to realize the diagnosis and modeling of the characteristics of complex grounded systems under pulsed currents,the traditional calculation model,Duhamel integral method and parameter approximation method of grounding system under impulse current are studied. Duhamel integral method is difficult to characterize complex circuit models,and parameter approximation method is hard to obtain ideal experimental data approximations. Based on the discrete network method,an improved calculation model for grounding system is proposed. The model established by this method allows it to directly use the modern algorithm for calculating the transient process of circuits. The results show that the method has high calculation accuracy and is easy to implement in computers. It can effectively avoid the defects in traditional modeling methods.